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Meme Media and a Meme Pool

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Title: Meme Media and a Meme Pool


1
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2
Meme Pool Architectures
3
  • In order to make pads work as memes in a society,
    we need a publication repository of pads where
    people in this society can publish any composite
    pads, down-load any published pads into their own
    local environment for their own use, recombine
    these down-loaded pads with each other or with
    their own pads to compose new pads, and replicate
    these composed pads to publish them for other
    peoples use.
  • The more useful or the more interesting pads are
    likely to be replicated more frequently and
    distributed more widely. Here we can see all the
    genetic operations necessary for genetic
    evolution, namely, replication, recombination,
    mutation, and natural selection. In this sense,
    this repository works as a meme pool of pads that
    work as meme media.

4
  • In this chapter, we will propose several
    different architectures for the publication and
    reuse of pads through the Internet.
  • These architectures provide different levels of
    pad publication facilities ranging from a pad
    catalog on a Web page to a marketplace of pads.
  • The former provides a catalog of pads in which a
    click of a pad picture leads to the download of
    the corresponding pad from a remote pad server.
  • The latter provides a virtual piazza where people
    can upload and download pads to and from the
    corresponding server through drag-and-drop
    operations.
  • This chapter also shows how meme media
    technologies can be directly applied to Web
    contents to make the Web work as a meme pool.

5
Pad Publication Repository and WWW
  • The evolution rate of a meme pool depends on the
    frequency and the variety of memetic
    recombination that are ruled by several factors.
  • These factors include
  • the number of people accessing this pool,
  • how easy for them to recombine memes, and
  • how often for them to encounter interesting
    memes.

6
  • There are three corresponding ways to accelerate
    the meme pool evolution.
  • To increase the number of people accessing the
    pool, we need to establish a worldwide repository
    of memes, and to make it easy to access this
    repository.
  • For the ease of meme recombination, we need to
    develop a user-friendly editing system for
    end-users to compose, to decompose, and to
    recombine memes.
  • Finally, to increase the chance for people to
    encounter interesting memes, we need to develop a
    good browser or a good reference service system
    for people to search the repository of memes for
    what they are interested in.

7
  • While the second requirement is fulfilled by the
    meme media architecture, the first and the third
    require a worldwide repository of memes, and a
    good browser and/or a good reference service
    system to access this repository.
  • In other words, we need to organize a marketplace
    where people can publish their achievements as
    pads, browse through all the pads published by
    other people, and reuse any of these pads for
    their own use in their own IntelligentPad
    environments.
  • Pads as meme media require another medium that
    works as their marketplace.

8
  • In addition to the above-mentioned three ways of
    accelerating the meme-pool evolution, we should
    not forget the fourth way that is based on a
    hypothesis of a punctuated equilibrium in
    population genetics.
  • For the acceleration of the meme-pool evolution,
    it is not a good strategy to provide a single
    monolithic large meme pool.
  • Instead, it is better to provide such a meme pool
    that enables people to dynamically develop
    smaller sub-pools for sub-communities, to
    cultivate a local culture in each of them, and to
    dynamically merge some of them.
  • The WWW fits this strategy due to its
    non-monolithic complex web structure.

9
  • To bring a punctuated equilibrium to the meme
    pool of pads, this marketplace needs to have a
    non-monolithic complex structure such as the Web.
  • Our IntelligentPad project set up the following
    four sub goals in 1993 to develop such
    marketplace systems.

10
  • The first system uses WWW and its browser such as
    Netscape Navigator or Microsoft Internet
    Explorer. While WWW works as a worldwide pad
    repository, Netscape Navigator or Internet
    Explorer provides a hypermedia catalog of pads to
    navigate this repository.
  • Each Web page describes various pads using texts
    and images.
  • Pad names in textual descriptions and
    display-snapshot images of pads work as special
    anchors. A mouse click on one of these special
    anchors will pop up an IntelligentPad window with
    a real working copy of the requested pad.
  • The original of this pad may be stored anywhere
    in the world. It is stored there using the
    exchange format representation.
  • When the anchor is clicked, the browser issues a
    file transfer request to the HTTP server at this
    remote site. After a while, the local Web browser
    receives this file, and then invokes the
    IntelligentPad system to reconstruct the pad
    using its exchange format representation.

11
  • The second system provides a special pad called a
    URLAnchorPad.
  • When mouse-clicked, a URLAnchorPad directly
    issues a URL (Universal Resource Locator) to the
    HTTP server to retrieve another composite pad
    from a remote site.
  • A URLAnchorPad, when pasted on another pad, works
    as a link anchor in a hypermedia network spanned
    across the Internet.

12
  • The third system provides a new Web browser that
    basically works in a similar way as Netscape
    Navigator and Internet Explorer. This browser is
    also a pad called an HTMLViewerPad. It allows us
    to publish any composite pads by embedding them
    in arbitrary Web pages.
  • You can publish any documents and tools as
    composite pads embedded in Web pages.
  • You may even publish a database client tool on a
    Web page.
  • Since an HTMLViewerPad is also a pad, you may
    embed a Web page in another Web page.
  • Different from Java applets, embedded pads can be
    copied and locally reused.
  • Different from ActiveX controls, embedded pads,
    after dragged out into a local environment from a
    Web page, can be decomposed and hence locally
    reused in recombination with other local pads, or
    even with those embedded in other Web pages.

13
  • The fourth system integrates the accounting,
    billing, and payment mechanism with the preceding
    three different pad distribution systems, which
    will be discussed in the next chapter.

14
Pad Publication and Pad Migration
  • IntelligentPad aims at the provision of social
    infrastructure for the distribution and exchange
    of various knowledge resources.
  • To achieve this goal, we have to solve the
    cross-platform reusability of pads.
  • Pads should be transportable across different
    platforms, and reusable in different
    environments.
  • To achieve this cross-platform reusability, we
    have to solve two problems, i.e.,
  • how to migrate each pad from one IntelligentPad
    system to another, and
  • how to cope with different platforms.

15
  • There are three levels of object migration across
    different systems.
  • The shallowest-level object migration assumes
    that the two systems share the same class
    library. In this case, the source system cannot
    send the destination any object whose class
    definition is not in the destination.
  • The middle-level object migration assumes that
    the two systems share only the basic common
    portion of the class library. It is further
    assumed in this case that each object definition
    only inherits its property from those classes in
    the basic common class library, but not from any
    classes outside of the basic portion of the class
    library. In this case, the source system can send
    any object to the destination.
  • The deepest-level object migration assumes no
    common class library. In this case, we have to
    migrate not only this object but also all the
    classes used in the definition of this object.

16
Web Pages as Pad Catalog
  • The existing Web browsers such as Netscape
    Navigator and Internet Explorer allow us to
    publish multimedia documents throughout the
    world.
  • They allow us to publish pad catalogs that show,
    for each pad, its features and hardcopy image.
  • The worldwide publication repository of pads can
    use this catalog publication function for its
    users to browse through pads published into this
    repository.

17
  • We assume that every site in the community of our
    concern installs an IntelligentPad system with
    the same class library.
  • Each Web page of a pad catalog to publish
    describes various pads using texts and images.
  • Pad names in textual descriptions and visual
    images of pads work as special anchors.
  • A mouse click on one of these special anchors
    will pop up a new window with a copy of the
    requested pad.
  • The original of this pad is stored in the
    destination file specified by the URL. This file
    may exist anywhere in the Internet.
  • The pad is stored in this file using its exchange
    format representation.
  • When the anchor is clicked, the Web browser
    issues a request to the Web server to transfer
    the destination file from a remote site.
  • When the Web browser at the client site receives
    this file, it invokes a special file loader in
    the local IntelligentPad system to reconstruct
    the pad using its exchange format representation.

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19
  • Such invocation requires a special mechanism to
    associate different types of anchors with
    different application programs to invoke.
  • The existing Web browsers have this facility. To
    identify each type of anchors, they use the file
    name extension of the destination file.
  • When registered to a Web browser, a file name
    extension works as an anchor type called a mime
    type. Each mime type can be associated with an
    application program to invoke.
  • Each pad catalog uses pad as the
    file-name-extension of pad files.

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21
  • The current version of IntelligentPad assumes
    that every site shares the same class library.
  • This assumption requires periodical update of the
    class library in each site. This update can be
    manually performed by accessing the on-line
    IntelligentPad system journal that is managed at
    a special site called the class-library-manager
    site.
  • WWW also simplifies this manual update procedure.
    You can just open the home page of the
    class-library-manager site, and click the
    version-update button on this page.
  • This anchor button specifies the URL of the
    system-update difference file. When clicked, this
    anchor fetches this file, and invokes the system
    update program. This invocation uses another file
    name extension ip as its mime type.

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23
  • WWW and its Web browsers also make it easy for
    end-users to publish pads into the worldwide
    repository.
  • IntelligentPad provides a special pad called a
    PublicationPad. You can drag and drop your pad
    onto this pad, which then saves this pad into a
    new file in the local Web server.
  • You have to specify this file name, while its
    extension is automatically set to pad.
  • The PublicationPad then pops up a text input pad,
    and asks you to input a description of this pad
    in HTML.
  • It then rewrites the HTML file storing your pad
    catalog to add the hardcopy image and the textual
    description of the pad you want to publish.
  • In addition to the anchors you specified in the
    description, the hardcopy of the pad also works
    as an anchor when this catalog is viewed through
    a Web browser.

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25
URL-Anchor Pads
  • Instead of using Web browsers, we can directly
    span hypermedia links among pads distributed
    across the Internet.
  • Anchors of links can be represented as pads.
  • To specify such a file, we can use a URL.
    IntelligentPad provides a new anchor pad called a
    URLAnchorPad that specifies its destination pad
    using the URL of its file.
  • When mouse-clicked, a URLAnchorPad directly
    issues an URL to an HTTP server to retrieve a
    specified composite pad from a remote site.
  • This resizable pad, when pasted on another pad,
    works as a link anchor in a hypermedia network
    spanned across the Internet. It can be made
    transparent, and can be pasted at arbitrary
    location on an arbitrary pad.

26
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27
HTMLViewerPad with Embedded Arbitrary Composite
Pads
  • An HTMLViewerPad basically works in a similar way
    as Netscape Navigator and Internet Explorer.
  • Furthermore, it allows us to publish any
    composite pads by embedding them in arbitrary Web
    pages.
  • Our pad distribution system uses the exchange
    format representation to embed arbitrary
    composite pads into HTML text files.
  • Each composite pad to be embedded is first stored
    in a file at an arbitrary site in the Internet
    using its exchange format representation.
  • The file name extension of this file must be
    specified as pad. Then a URL pointer to this
    file is embedded in an HTML text, and this text
    is published as a Web page.

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29
  • When an HTMLViewerPad accesses a Web page without
    any embedded pads, it works as a conventional
    browser such as Netscape Navigator and Internet
    Explorer.
  • When an HTMLViewerPad accesses a Web page with
    some embedded pads, it treats each embedded pad
    as follows.
  • When it receives the save format representation
    file of an embedded pad from a remote site, it
    first treats this pad as a blank figure of the
    same size. This figure makes a space of this size
    in the Web page.
  • Then the HTMLViewerPad constructs the
    corresponding composite pad, and put this pad in
    the saved space in the Web page.
  • Any page scroll of this Web page also moves this
    pad on the HTMLViewerPad so that it always
    exactly sits on the space saved for this pad.

30
  • You can publish any documents and tools as
    composite pads embedded in Web pages.
  • You may even publish HTMLViewerPads accessing
    different Web pages by embedding them in another
    Web page.
  • You may also publish a database client tool on a
    Web page.
  • The next figure shows a Web page with an embedded
    composite pad that works as a form interface to a
    remote database server. The site of this database
    server may be different from the Web page site.
  • You can specify a query on this form interface to
    access this database.

31
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32
New Publication Media
  • The HTMLViewerPad allows us to publish and
    acquire any objects as composite pads to and from
    Web servers.
  • These servers form worldwide publication
    repositories.
  • Objects to publish include multimedia documents,
    application programs working as interactive
    tools, client tools accessing remote servers, and
    client tools communicating with remote
    application programs.
  • When applied to scientific publication, this new
    publication repository allows us to publish
    scientific papers together with reusable related
    data, reusable related tools, and remotely
    accessible related database services by embedding
    all of them in the documents.

33
  • The nuclear reaction database stores a collection
    of data sets. Each data set is defined as a data
    table from a series of nuclear reaction
    experiments.
  • Data sets have attributes. Different data sets
    may have different sets of attributes.
  • To store these data sets in a relational
    database, we have to represent each data set as a
    set of triples consisting of its data set ID, one
    of its attributes, and its value of this
    attribute. This set includes all the triples for
    all of its attributes.
  • We used UniSQL database management system, and
    defined on it a single relation with three
    attributes, i.e., data set ID, attribute name,
    and attribute value to store all these triples
    for all the data sets.

34
  • Researchers in nuclear reaction physics use this
    database to pick up some set of data sets
    satisfying some condition on their attributes
    such as the reaction type, the incident particle,
    the target nucleus, etc.
  • Then they analyze the picked-up data sets using
    some tools, or compare them with others.
  • The composite pad in the next figure allows you
    to access the remote nuclear reaction database
    through the Internet.
  • It gives you the distribution of data sets with
    respect to two arbitrarily selected attributes.
  • Here in this example, the X coordinate represents
    a set of different incident particles, while the
    Y coordinate represents a set of different target
    nuclei.
  • Each dot in this chart is actually a pad. We call
    it a data-set pad. You may click one of these
    data-set pads to show its detail information as
    shown in the display snapshot image of this tool.

35
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36
  • Researchers can easily select one of these
    data-set pads and retrieve its contents from the
    same database using another tool pad.
  • The HTMLViewerPad in the next figure shows
    another page of a research paper that includes
    this tool pad.
  • You may drag and drop the selected data-set pad
    into this tool pad.
  • This tool accesses the same remote database and
    retrieves its content as a pad.

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38
  • You may open one more different Web page to the
    right of this Web page. This new Web page shows
    another researchers document that includes a
    chart drawing tool pad.
  • You may move the data-set content pad to this
    chart tool to plot its content data. This chart
    shows an angular distribution of reaction
    cross-sections.

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40
  • Different from Java applets and ActiveX controls,
    embedded pads can be copied and locally reused in
    combination with other local pads.
  • The recombination of media objects in the market
    with local pads is fundamental for them to work
    as meme media.
  • Java and ActiveX inherently lack this function.

41
Publication and reuse of documents, tools,
services, and agents
  • Objects to be published include multimedia
    documents, application programs working as
    interactive tools, client tools accessing remote
    servers, and client tools communicating with
    remote application programs.
  • The third kind of objects can be regarded as
    services. Remote servers provide these services.
    Their users can appreciate these services through
    their client tools published as pads.
  • An object of the fourth kind works as an agent.
    The person who published this agent provides an
    application program. The published pad that works
    as an agent works as a proxy of this application
    program. It communicates with this program
    through Web servers by using CGI commands.
  • Such an agent pad, when its page is opened,
    requests its user for a reply, or for some
    operation on this agent pad. For example, it may
    ask the user to drag out itself and to drop
    itself on a specified local pad to acquire local
    information through this pad. The agent pad can
    send back this acquired information to its remote
    application program. It may even be able to
    delete itself when its mission is completed.

42
  • Service publication can even publish
    computer-controlled hardware facilities.
  • Suppose that your institute has a fully
    computer-controlled material-synthesizer system
    with various measurement tools to analyze
    synthesized materials. Its synthesis process is
    fully controlled by a computer through a large
    number of parameters. Its measurement tools are
    also fully controlled by the same computer
    through their parameters, and the measured
    results are monitored by the same computer.
  • If you develop proxy pads to communicate with the
    control and monitor programs of this system and
    its measurement tools, you can compose console
    panels for these facilities as composite pads,
    and publish them by embedding them in your Web
    pages.
  • This allows people all over the world to utilize
    your facilities.

43
  • This allows material scientists to use various
    public facilities distributed all over the world
    one after another to conduct their research
    projects.
  • A researcher in Singapore may synthesize a new
    material using a facility in US, measure their
    characteristics, and then analyze the measured
    data on a super computer installed in Japan.
  • The measurement data are also transported as a
    pad from one site to another site, from one Web
    page to another Web page or to a local
    environment.
  • Researchers may even pick up some components of
    these published facilities, recombine them to
    compose new facilities for their use, and publish
    these new tools for their reuse by others.

44
Annotation on Web Pages
  • Digital technology potentially allows us to
    overlay a transparent or translucent sheet for
    annotation on the original text, which may
    protect both the original and its appearance from
    any damage.
  • In the IntelligentPad system architecture, the
    development of such a transparent or translucent
    pad for annotation is quite an easy task.

45
  • The next figure shows a Web-annotator composed
    with an IEPad and a WebAnnotationPad.
  • An IEPad is a pad that is obtained by wrapping
    Internet Explorer with a pad wrapper. It has
    URIaddress slot to hold the URl of the current
    page.
  • A WebAnnotationPad has a double layered structure
    with its base layer and its surface layer. It has
    three URI slots, originalURIaddress slot (,
    which works as the primary slot),
    annotationURIaddress slot, and associationURI
    slot that respectively hold the original pages
    URI address, the URI of the current annotation
    file, and the URI address of a URI conversion
    service converting each original pages URI to
    the URI of the corresponding annotation file.
  • A WebAnnotationPad has 3 different operation
    modes, namely, the transparent mode, the
    translucent mode, and the hiding mode.

46
  • The surface layer works as a transparent or
    translucent film covering the base layer and its
    child pads if any.
  • In its transparent mode, a WebAnnotationPad makes
    its surface layer inactive, and the background of
    this layer transparent, only showing what are
    drawn or pasted on this layer every user event,
    including pad pasting events, passes through the
    surface layer. You may use this mode to paste an
    IEPad directly on the base layer of a
    WebAnnotationPad with its connection to
    originalURIaddress slot this IEPad is inserted
    between the base layer and the surface layer.
  • In its translucent mode, a WebAnnotationPad makes
    its surface layer active, and the background of
    this layer translucent only those user events
    that are not processed by this layer passes
    through the surface layer.
  • In its hiding mode, a WebAnnotationPad makes its
    surface layer, together with all the child pads
    of this layer, inactive and invisible every user
    event passes through the surface layer.

47
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48
  • In its translucent mode, a WebAnnotaionPad allows
    you to paste any pad on its surface layer.
  • The pasted pad works as a child pad of the
    surface layer.
  • Any pad pasted on a WebAnnotationPad in its
    transparent or hiding mode becomes a child of the
    topmost pad at this location under the surface
    layer.
  • The surface layer also works as a drawing tool.
    This function allows you to draw any figures as
    annotations to the Web page shown by the inserted
    IEPad.
  • When an inserted IEPad scrolls its page, the
    WebAnnotationPad also scrolls its surface layer
    for the same distance so that every child pad and
    every figure on the surface layer keep their
    original relative locations on the Web page shown
    by the inserted IEPad.

49
  • Each WebAnnotationPad has its associated local or
    remote file specified by the URI address stored
    in annotationURIaddress slot, and allows you to
    save its annotation information there, including
    its child pads and annotation figures, together
    with the URI of the Web page shown by the
    inserted IEPad.
  • Each WebAnnotationPad has another slot register
    for an external event to make it save its current
    state to its file.
  • When we change the URI of the inserted IEPad,
    this new URI is informed by this IEPad to the
    base layer of the WebAnnotationPad through
    originalURIaddress. Then the WebAnnotationPad
    accesses the URI conversion service specified by
    associationURI slot with the value of
    originalURIaddress slot, sets the returned
    address, if any, in annotationURIaddress slot,
    and accesses this address to obtain the current
    annotations on this original page.

50
  • A reference to any object as an annotation may
    use an AnnotationURIAnchorPad with the URI of
    this object.
  • You may paste such an AnnotationURIAnchorPad at
    any location on a WebAnnotationPad in its
    translucent mode with a connection to either
    originalURIaddress slot or associationURIaddress
    slot.
  • For the selection of originalURIaddress slot, a
    click of such an AnnotationURIAnchorPad sets its
    content URI to originalURIaddress slot of the
    WebAnnotationPad, which tells the inserted IEPad
    to read the new URI both the inserted IEPad and
    the WebAnnotationPad will respectively load the
    corresponding Web page and annotation
    information.

51
  • If you connect an AnnotationURIAnchorPad to
    associationURIaddress slot, then the
    WebAnnotationPad uses the URI sent from the
    anchor pad to access a different URI conversion
    server for converting the current original pages
    URI to a corresponding annotation files URI.
  • This mechanism is used to jump to a different
    users annotation on the same original page.
  • The previous figure shows an annotative comment
    Get more detail information! with an arrow
    pointing to a system name in the Web page. It
    also has an AnnotationURIAnchorPad with a caption
    Ive got some. See this page, which points to
    another Web page. When clicked, it sets a new URI
    to the WebAnnotationPad and its inserted IEPad.

52
Piazza as a Meme Pool
  • Pad publication using HTMLViewerPads require the
    writing of an HTML definition to embed each
    composite pad in a Web page.
  • Users like to use drag-and-drop operations not
    only to retrieve pads from WWW but also to
    publish pads to WWW.
  • They like to use a modeless browser to perform
    both the retrieval and publication seamlessly
    without changing the system mode.

53
  • Furthermore, the HTMLViewerPad as well as other
    currently available Web browsers does not allow
    any user to publish his or her own information in
    anothers Web pages, nor to span any links from
    anothers Web pages to his or her own Web pages.
  • Each user has to ask the owner of the Web page by
    sending, say, an e-mail to include his or her own
    information there or to span a link from this
    page to his or her own Web page.
  • This relation between users who want to publish
    their information and the owners of Web pages is
    similar to the relation between tenants and
    owners.
  • Each tenant is required to make a contract with
    the owner of the building in which he or she
    wants to open his or her store.

54
  • While the owner-tenant system works well for
    owners to supervise the clustering of similar
    information contents, there is another way of
    forming a marketplace, in which a large public
    space is provided for people to freely open their
    stores.
  • We also like to provide this kind of worldwide
    publishing repository of pads in which people can
    freely publish their pads for others to freely
    reuse them.

55
  • Piazza Web is a world-wide web of piazzas, each
    of which works as such a marketplace.
  • We can browse through Piazza Web, using a
    PiazzaBrowserPad.
  • Each piazza has a corresponding file that stores
    a set of pads together with their geometrical
    arrangement. Such files are stored in special
    remote servers called Piazza servers.
  • Each piazza is also represented as a pad called a
    PiazzaPad.
  • Pads can be drag-and-dropped to and from a
    PiazzaPad to upload and download pads to and from
    the associated remote server file.
  • When a PiazzaPad is opened, all the pads
    registered to the associated server file are
    immediately downloaded onto this pad, arranged in
    their registered locations, and become available.
  • A PiazzaPad has a slot to specify a piazza server
    with its URL address. When given an update
    message, a PiazzaPad saves all the pads on itself
    with their current states and current locations
    into the corresponding server.

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57
  • When given a new URL address, a PiazzaBrowserPad
    either generates a new PiazzaPad on itself or
    uses the old PiazzaPad, depending on its
    specified mode, and sets this URL address to the
    file address slot of the PiazzaPad to download
    the registered pads.
  • An entrance link to a piazza is represented by an
    AnnotationAnchorPad, and can be put on another
    piazza to define a link, with its connection to
    the file address slot of the PiazzaPad.
  • When clicked, the AnnotationAnchorPad sends its
    stored URL address to the file address slot of
    the underlying PiazzaBrowserPad, which then opens
    this piazza.

58
  • A PiazzaBrowserPad has a save slot, which, when
    accessed by a set message from, say, a buttonPad
    connected to this slot, sends an update message
    to its child PiazzaPad to make it save its child
    pads to the server.
  • Users are welcome to install their Piazza servers
    anywhere, anytime, and to publish their client
    pads.
  • Piazza enables end users to open their own
    gallery of pads on the Internet, or to exhibit
    their pads in some other private or public space.
  • Such pad galleries work as flea markets, shops,
    shopping centers, community message boards,
    community halls, or plazas.
  • Some piazzas may be for personal use, while some
    others may be shared by communities.
  • Some piazzas may be shared by more than one
    community, while some others may be open to the
    public.

59
  • Transportation of pads undefined at their
    destination requires their cross-platform
    migration their execution on the destination
    platform requires that all the libraries
    necessary for their execution should be available
    there in advance.
  • These libraries include pad definition libraries,
    API libraries, and class libraries. These are
    defined as DLLs (Dynamic Link Libraries), and
    dynamically called when required.
  • Migration of a new pad to a different platform
    requires migration of all the required DLLs that
    the destination lacks.
  • Pads that someone has uploaded to a PiazzaPad can
    be downloaded from the same PiazzaPad and
    executed if and only if the destination platform
    has all the required DLLs.

60
  • Each PiazzaPad allows privileged users to upload
    a new pad together with its required DLLs.
  • When another user opens this PiazzaPad, it checks
    if the destination platform has all the required
    DLLs.
  • If yes, this user can drag this pad out of the
    PiazzaPad.
  • If not, the PiazzaPad asks the user if he or she
    wants to download the missing DLLs.
  • The automatic DLL migration by Piazza systems
    simplifies the distribution of pads among users.

61
Re-editing and Redistributing Web Contents as
Meme Media Objects
62
  • Meme media and meme pool architectures will play
    important roles when they are applied to a
    reasonably large accumulation of intellectual
    resources.
  • The current situation of the Web satisfies this
    condition.
  • This section focuses on how to convert the
    intellectual resources on the Web to meme media
    objects, while the preceding sections in this
    chapter have focused on how to convert Web
    technologies to implement meme pools for the
    intellectual resources represented as pads.
  • In the latter approach, we cannot deal with
    legacy Web contents as memes, i.e., as
    re-editable and redistributable objects.
  • In the former approach, on the other hand, we can
    extract any components of Web pages including
    multimedia, application tool, and/or service
    components, recombine them to define a new layout
    and a new composite function, and publish the
    result as a new Web page.

63
The re-editing of Web contents requires
  • Easy extraction of an arbitrary Web-document
    portion together with its style.
  • To keep live contents alive after arbitrary
    re-editing.
  • Easy re-editing of Web contents that may be
    extracted from different Web pages by combining
    them together to define both a new layout and a
    new functional composition.
  • Easy redistribution of re-edited Web contents
    across the Internet.
  • Easy conversion of re-edited Web contents to HTML
    format
  • Easy registration of an HTML document to an HTTP
    server.

64
Meme media technologies provide ...
  • The wrapping of an arbitrary object with a
    standard visual wrapper to define a media object
    having a 2D representation on a display screen
  • A wrapped object may be a multimedia document, an
    application program, or any combination of them.
  • The re-editing of meme-media objects
  • You can visually combine a meme-media object with
    another meme-media object on the display screen
    by mouse operations, and define a functional
    linkage between them.
  • You may take out any component meme-media object
    from a composite meme-media object.
  • The re-distribution of meme-media objects
  • Meme-media objects are persistent objects that
    you can send and receive for their reuse, by
    e-mail for example, across the Internet.

65
  • Here we use IntelligentPad technologies to
    achieve the first four of the above mentioned six
    capabilities. Now our goal can be paraphrased as
    follows
  • How to extract any portion of a Web document, and
    to wrap it with a pad wrapper with some slot
    definitions.
  • How to incorporate periodic server-access
    capabilities in the wrapping of a live Web
    content.
  • How to convert a composite pad to an HTML
    document, and to register this to an HTTP server.

66
XML and pads
  • The conversion of Web document components to pads
    requires the way to represent HTML or XHTML
    documents as pads.
  • While the HTMLviewerPad can represent any HTML
    document as a pad, we still need a way to make
    any HTML component of such a pad work as a slot.
    The value of such a slot is the value of the
    corresponding HTML component.

67
  • The display object and the model object of a
    primitive pad are usually defined as C code,
    which makes it difficult for non-programmers to
    develop a new pad.
  • Some pads have very simple internal mechanism
    that requires no coding. They include multimedia
    documents with some parameters exported through
    their pad slots.
  • For the definition of such a document, we may use
    XHTML, or a pair of XML and XSL to define its
    content and style, which requires no programming
    expertise.
  • You may specify any of its phrases enclosed by a
    begin-tag and an end-tag to work as a slot value.
  • An IEPad, a special HTMLviewerPad, when provided
    with document contents in XML and a style in XSL,
    generates the corresponding XHTML text to view on
    itself.
  • It also generates a slot for each specified
    phrase in the original XML or XSL texts.

68
  • The next left figure shows a parameterized XHTML
    that displays any text string in the specified
    orientation.
  • Two parameters are parenthesized with tags to
    specify that they work as slots.
  • The next right figure shows its viewing by an
    IEPad, which has two child pads one is used to
    input a string, while the other is to specify the
    angle.
  • In addition to these functions, an IEPad allows
    us to embed any composite pad in an XHTML text
    using a special tag, and generates this pad on
    itself when viewing this XHTML text.
  • The XHTML text in this example embeds a composite
    pad working as an analog clock.

69
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70
Extraction of an Arbitrary Web Contents as 2D
Meme Media Objects
  • Web documents are defined in HTML format.
  • An HTML view denotes an arbitrary HTML document
    portion represented in the HTML document format.
  • The pad wrapper to wrap an arbitrary portion of a
    Web document needs to be capable of both
    specifying an arbitrary HTML view and rendering
    any HTML document.
  • We call this pad wrapper an HTMLviewPad, which is
    different from an HTMLviewerPad.
  • Its rendering function is implemented by wrapping
    a legacy Web browser such as Netscape Navigator
    or Internet Explorer.

71
  • The specification of an arbitrary HTML view over
    a given HTML document requires the capability of
    editing the internal representation of HTML
    documents, namely, DOM trees.
  • The DOM tree representation allows you to
    identify any HTML-document portion, which
    corresponds to a DOM tree node, with its path
    expression.
  • The next figure shows an HTML document with its
    DOM tree representation.
  • The highlighted portion in the document
    corresponds to the highlighted node whose path
    expression is /HTML0/BODY0/TABLE0/TR1/TD1
    .
  • A path expression is a concatenation of node
    identifiers along a path from the root to the
    specified node.
  • Each node identifier consists of a node name,
    i.e., the tag given to this node element, and the
    number of its sibling nodes located to the left
    of this node.

72
Extraction of a Web Page Portionas a View
Document
Client Document (HTML)
HTML view
Extracted information
Delete (Remove)
Cut out (Extract)
Description of the editing process
Description of view definition
View-Definition Code
doc getHTML(http//www.abc.com/,null)
Retrieval Code
view doc .EXTRACT( editing location )
.REMOVE( editing location )
View-Editing Code
73
Node Identification
Node identifier to identify any object in a
document
/HTML0/BODY0/TABLE0/TR1/TD1
ltHTMLgt
ltHEADgt
ltBODYgt
/ node-name index / node-name index1-
index2 / node-name / node-name / text()
/ node-name / attr( attr-name )

ltTABLEgt
0
2
1
ltTRgt
ltTRgt
ltTRgt
ltTDgt
ltTDgt
ltTDgt
ltTDgt
ltTDgt
ltTDgt

ltBgt
ltBgt
ltBgt

????
TOPIX
12,969.05
1,300.98
DOM Tree
74
  • Sometimes you may need to specify, among sibling
    nodes, a node with a specific character string as
    a substring of its textual contents. You may
    specify such a node as tag-nameMatchingPattern
    index, where MatchingPattern is the specified
    string, and index selects one node among those
    siblings satisfying the condition.
  • You may need to extract some character string in
    a text node.
  • Its path expression locates this node, but does
    not locate such a substring.
  • We will extend the path expression to use a
    regular expression for locating such a substring
    in a text node.
  • For the DOM tree in the next figure, the node
    /HTML0/BODY0/P/txt(. (\d\d\d\d) .)
    specifies the virtual node shown in this figure.

75
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76
  • The definition of an HTML view consists of the
    specification of the source document, and a
    sequence of view editing operations.
  • The specification of a source document uses its
    URL. Its retrieval is performed by the function
    getHTML in such a way as
  • doc getHTML(http//www.abc.com/index.html,
    null).
  • The second parameter will be used to specify a
    request to the Web server at the retrieval time.
  • Such requests include POST and GET. The retrieved
    document is kept in DOM format.

77
Extraction of a Web Page Portion
Wrapper Object(HTMLviewPad)
Extraction
Drag
URL
http//weather.yahoo.co.jp/weather/
Editing code
CLIP(/HTML0/BODY0/TABLE0/TR1)
ltHTMLgt
ltHEADgt
ltBODYgt

ltTABLEgt
ltTRgt
ltTRgt
ltTRgt
ltTDgt
ltTDgt
ltTDgt
ltTDgt
ltTDgt
ltTDgt
HTMLviewPad

ltBgt
ltBgt
ltBgt

78
  • The editing of an HTML view is a sequence of DOM
    tree manipulation operations selected out of the
    followings
  • EXTRACT Delete all the nodes other than the sub
    tree with the specified node as its root.
  • REMOVE Delete the sub tree with the specified
    node as its root.
  • INSERT Insert a given DOM tree at the specified
    relative location of the specified node. You may
    select the relative location out of CHILD,
    PARENT, BEFORE, and AFTER.

79
Editing Operators
EXTRACT( node identifier )
EXTRACT(?)
REMOVE( node identifier )
ltHTMLgt
ltBODYgt
INSERT( node identifier, document , relation)
REMOVE(?)
2nd parameterdocument to insert3rd
parameterwhere to insert lt CHILD
BEFORE AFTER PARENT gt
CHILD
BEFORE
AFTER
PARENT
doc
ltBODYgt
ltBODYgt
ltBODYgt
ltBODYgt
INSERT(?, doc , X )
80
  • An HTML view is specified as follows
  • defined-view source-view.DOM-tree-operation(n
    ode),
  • where source-view may be a Web document or
    another HTML document, and node is specified by
    its extended path expression.
  • .
  • The following is an example view definition with
    the nested use of the above syntax
  • view1 doc
  • .EXTRACT(/HTML/BODY/TABLE0/)
  • .EXTRACT(/TABLE0/TR0/)
  • .REMOVE(/TR0/TD1/)

81
  • You may also specify two sub trees extracted
    either from the same Web document or from the
    different Web documents, and combine them to
    define a view.
  • doc getHTML(http//www.abc.com/index.html,
    null)
  • view2 doc
  • .EXTRACT(/HTML/BODY/TABLE0/)
  • .EXTRACT(/TABLE0/TR0/)
  • view1 doc
  • .EXTRACT(/HTML/BODY/TABLE0/)
  • .INSERT(/TABLE0/TR0/, view2, BEFORE)

82
  • You may create a new HTML document and insert it
    to an HTML document.
  • doc1 getHTML(http//www.abc.com/index.html,
    null)
  • doc2 createHTML(ltTRgtHello Worldlt/TRgt)
  • view1 doc1
  • .EXTRACT(/HTML/BODY/TABLE0/)
  • .INSERT(/TABLE0/TR0/, doc2, BEFORE)

83
Code Description and Evaluation
HTML view
Client Document
Web Server
EditingProcessor
Parser
HTTP Access
HTML
EXTRACT?/HTML/BODY//TABLE0REMOVE
?/TABLE0/TR1
http//www.abc.com/
View Evaluator
View-Definition Code
doc getHTML(http//www.abc.com/,null) view
doc .EXTRACT(/HTML/BODY//TABLE0)
.REMOVE(/TABLE0/TR1)
84
Direct editing of HTML views
  • Instead of specifying a path expression to
    identify a DOM tree node, we will make the
    HTMLviewPad to dynamically frame different
    extractable document portions for different mouse
    locations so that its user may move the mouse
    cursor around to see every extractable document
    portion.
  • This method, however, cannot distinguish
    different HTML objects with the same display
    area. To identify such an object, we use an
    additional consol panel with two buttons and the
    node specification box.
  • The node specification box changes its value
    while you move the mouse to select different
    document portions. The first button is used to
    move to the parent node in the corresponding DOM
    tree, while the second to move to the first child
    node.

85
Automatic Code Geneation
HTMLviewPad
Step1 document selection
getHTML(http//www.abc.com/,null)
Step2 specification of a editing location
  • node identification

/TABLE0/TR0/TD1
Step3 execution of the editing
  • generation of a view editing code

86
  • When the HTMLviewPad frames what you want to
    extract, you can drag the mouse to create another
    HTMLviewPad with this extracted document portion.
    The new HTMLviewPad renders the extracted DOM
    tree on itself.
  • The next figure shows an example extraction using
    such a mouse-drag operation, which internally
    generates the following edit code.
  • doc getHTML(http//www.abc.com/index.html,
    null)
  • view doc
  • .EXTRACT(/HTML/BODY/TABLE0/)

87
Editing Operation1 (Live-Cut)
Drag Out
HTMLviewPad
A copy of the code
HTMLviewtPad
doc getHTML(http//www.abc.com/,null) view
doc .EXTRACT(/HTML/BODY//
.EXTRACT(/HTML/BODY//TABLE0)
Automatically generated code
88
  • The HTMLviewPad provides a pop-up menu of
    view-edit operations including EXTRACT, REMOVE
    and INSERT.
  • After you select an arbitrary portion, you may
    select either EXTRACT or REMOVE.
  • The next figure shows an example remove
    operation, which generates the following code.
  • doc getHTML(http//www.abc.com/index.html,
    null)
  • view doc
  • .EXTRACT((/HTML/BODY/TABLE0/)
  • .REMOVE(/TABLE0/TR1/)

89
Editing Operation 2
extract delete


HTMLviewPad
EDIT
REMOVE
HTMLviewPad
CLIP
Menu Selection
doc getHTML(http//www.abc.com/,null) view
doc .EXTRACT(/HTML/BODY//TD2//TABLE0/
)

Generated code
.REMOVE(/TABLE0/TR1/)
90
  • The INSERT operation uses two HTMLviewPads
    showing a source HTML document and a target one.
  • You may first specify INSERT operation from the
    menu, and specify the insertion location on the
    target document by directly specifying a document
    portion and then specifying relative location
    from a menu including CHILD, PARENT, BEFORE, and
    AFTER.
  • Then, you may directly select a document portion
    on the source document, and drag and drop this
    portion on the target document.

91
  • The next figure shows an example insert
    operation, which generates the following code,
    where the target HTMLviewPad uses a different
    name space to merge the edit code of the
    dragged-out HTMLviewPad to its own edit code
  • Aview Adoc
  • .EXTRACT(/HTML/BODY//TD1//TABLE0)
  • .REMOVE(/TABLE0/TR1/)
  • view doc
  • .EXTRACT(/HTML/BODY//TD0//TABLE0/)
  • .REMOVE(/TABLE0/TR1/)
  • .INSERT(/TABLE0, Aview, AFTER)

92
Editing Operation 3
insert
Drop In

CHILD
BEFORE
AFTER
PARENT
HTMLviewPad
HTMLviewPad
Menu Selection( Insert Type)
Combination of codes
doc getHTML(http//www.abc.com/,null)Ad
oc getHTML(http//www.abc.com/,null)Aview
Adoc .EXTRACT(/HTML/BODY//TD1//TAB
LE0/) .REMOVE(/TABLE0/TR1/)
view doc .EXTRACT(/HTML/BODY//TD0/
/TABLE0/) .REMOVE(/TABLE0/TR1/)
.INSERT(/TABLE0,Aview,AFTER)
Adoc getHTML(http//www.abc.com/,null)Av
iew Adoc .EXTRACT(/HTML/BODY//TD1/
/TABLE0/) .REMOVE(/TABLE0/TR1/)
Generated code
.INSERT(/TABLE0,Aview,AFTER)
93
Automatic generation of default slots
  • The HTMLviewPad allows you to map any node values
    of its view and any events on its view to its
    newly defined slots.
  • The definition of such a node-slot mapping takes
    the following form
  • MAP(ltnodegt, NameSpace),
  • where ltnodegt is specified by its path expression
    and NameSpace defines a slot name.
  • An example of such a mapping is as follows
    MAP(/HTML/BODY/P/txt( ), value)

94
Data Mapping for Defining Slots
Mapping view information to slots
View-Document
RenderingEngine
ltHTMLgt
View rendering
ltBODYgt
Event
Mapping of node values
MappingEngine
MappingCode
Mapping DATA
Mapping-definition code
MAP( node-identifier , slot-name)
95
  • Depending on the node type, the HTMLviewPad
    changes the node value evaluation to map the most
    appropriate value of a selected node to a newly
    defined slot.
  • We call these evaluation rules node-mapping
    rules.
  • Each node-mapping rule has the following syntax
  • target-object gt naming-rule(data-type)ltMappingTy
    pegt
  • naming-rule naming rule for the new slot
  • data-type data type of the slot
  • MappingType ltIN?OUT?EventListener?EventFiregt

96
Slot Mappingmechanism for reusing Web resources
Wrapper (HTMLviewPad)
Slot
Textual object
Numerical value
Pad
12,969.05
/HTML//content
TOPIX 1,311.49 ???? 12969.05 ?????? 57.94
Table object
Table data
/HTML//table
Tag descriptor format
InputField form ?Inc.
Form object
Button form false
Submit event http//xxx/xxx.cgi?a?
/HTML//form
anchor object
Character data Yahoo Japan
Yahoo Japan
OnClick event http//www.yahoo.co.jp
/HTML//a
97
Text nodes
  • For a general node such as lt/HTML//txt( )gt,
    lt/HTML//attr( )gt, or lt/HTML//P/gt, the
    HTMLviewPad automatically defines a default slot,
    and sets the text in the selected node to this
    slot.
  • If the text is a numerical string, it converts
    this string to a numerical value, and sets this
    value to the slot.
  • a text in the selected node (character string)
  • gt NameSpaceText(string)ltOUTgt
  • a text in the selected node (numerical string)
  • gt NameSpaceText(number)ltOUTgt

98
Node Mapping Rules(1)
Different mapping for different node types
Node mapping rules
Slot
Mapping Type
MAP( /HTML/BODY//P/ txt() , Value1)
Slot Type
Numerical value type
12,969.05
ltPgt12,969.05lt/Pgt
ltOUTgt
Mapping value(Slot value)
Value1Text
ViewportPad
HTML Source
Slot name
MAP( /HTML/BODY//TABLE0 , Stock)
ltTABLEgtltTRgtltTDgtTOPIXlt/TDgtltTDgt1,311.49lt/TDgtlt/TRgt
ltTRgtltTDgt????lt/TDgtltTDgt12,969.05lt/TDgtlt/TRgt
ltTRgtltTDgt??????lt/TDgtltTDgt57.94lt/TDgtlt/TRgt
lt/TABLEgt
Character string type (CSV)
TOPIX ,1,311.49???? ,12969.05?????? ,57.94
ltOUTgt
StockData
99
Table nodes
  • For a table node such as lt/HTML//TABLE/gt, the
    HTMLviewPad converts the table value to its CSV
    (Comma-Separated Value) representation, and
    automatically maps it to a newly defined default
    slot of text type.

100
Meme Media Meme Pool
meme pool
userB
drag drop
userA
drag drop
redistribution
reediting
userC
101
Anchor nodes
  • For an anchor node such as lt/HTML//A/gt, the
    HTMLviewPad automatically performs the following
    three mappings to define three default slots
  • a text in the selected node
  • gt NameSpaceText(string, number)ltOUTgt
  • href attribute of the selected node
  • gt NameSpacerefURL(string)ltOUTgt
  • URL of the target object
  • gt NameSpacejumpURL(string)ltEventListenergt

102
  • For example, let us consider a case in which we
    extract an anchor defined as follows
  • ltA href ./next.htmlgt
  • Next Page
  • lt/Agt
  • The first mapping sets the text Next Page to a
    string ( or number ) type default slot
    NameSpaceText.
  • The second mapping sets the href ./next.html to
    a string type default slot NameSpacerefURL.
  • The third mapping has the EventListener type.
    Whenever the anchor is clicked, the target URL is
    set to a string-type default slot
    NameSpacejumpURL.

103
Form nodes
  • For a form node such as lt/HTML//FORM/gt, the
    HTMLviewPad automatically performs the following
    three mappings to define three default slots
  • the value attribute of the INPUT node with
    the name attribute in the
  • selected node
  • gt NameSpaceInput_type_name(string,
    number)ltIN, OUTgt
  • Submit action
  • gt NameSpaceFORM_Submit(boolean)ltEventFiregt
  • the value obtained from the server
  • gt NameSpaceFORM_Request(string)ltEventListener
    gt
  • type lttext?pasword?file?checkbox?radio?hidden?s
    ubmit?reset?button?imagegt
  • name ltnamegt attribute in the INPUT node

104
  • For example, let us consider a case in which we
    extract a form defined as follows
  • ltFORM action./searchgt
  • ltINPUT Typetxt namekeyword gt
  • ltINPUT Typesubmit valuesearchgt
  • lt/FORMgt
  • The first mapping rule for a form sets the input
    keyword to a string (or number ) type default
    slot NameSpaceInput_text_keyword.
  • The second mapping rule is an EventFire-type
    mapping. Whenever a TRUE is set to a Boolean type
    default slot FORM_Submit, the HTMLviewPad
    triggers a form-request event.
  • The third mapping has the EventListener type.
    Whenever an event to send a form request occurs,
    the HTMLviewPad sets the corresponding query to a
    string type default slot NameSpaceFORM_Request.

105
Node Mapping Rule (2)
MAP( /HTML/BODY//A0 , Link1)
Character string type
Next Page
ltOUTgt
Link1Text
ltA href ./next.htmlgtNext Pagelt/Agt
Character string type
./next.html
ltOUTgt
Link1refURL
On jumping
Character string type
http//www.abc.com/next.html
ltEventListenergt
Link1jumpURL
MAP( /HTML/BODY//FORM0 , SearchForm)
Character string type
ltIN,OUTgt
??
SearchFormInput_text_keyword
ltFORM action./searchgtltINPUT Typetxt
namekeyword gtltINPUT Typesubmit
value??gtlt/FORMgt
Boolean type
ltEventFiregt
Query issuing event
true
SearchForm submit
Character string type
ltEventListenergt
http//www.abc.com/search?keyword??
On issuing a query
SearchForm request
106
Meme Media Meme Pool
meme pool
userB
drag drop
userA
drag drop
redistribution
reediting
userC
107
  • Each HTMLviewPad has the additional following
    four default slots.
  • The UpdateInterval slot specifies the time
    interval for the periodical polling of referenced
    HTTP servers. A view defined over a Web document
    refresh its contents by periodically retrieving
    this Web document in an HTTP server.
  • The RetrievalCode slot stores the code to
    retrieve the source document.
  • The ViewEditingCode slot stores the view
    definition code.
  • The MappingCode slot stores the mapping
    definition code.
  • The HTMLviewPad updates itself by accessing the
    source document, whenever either the
    RetrievalCode slot or the ViewEditingCod slot
    is accessed with a set message, the interval
    timer invokes the polling, a user specifies its
    update, or it becomes active after its loading
    from a file.

108
Live Document Framework
Extraction of live knowledge resources to make
them work as pads
9791.09
\12,841.76
Dow Jones average
Nikkei average
Estimate
  • Reuse of live knowledge on the Web

?? \12,841.76
?? 9791.09
total in
currency rate
  • Integration of live knowledge resources from
    different web pages

total in yen
109
Visual definition of slots for extracted Web
contents
  • Our HTMLviewPad also allows users to visually
    specify any HTML-node to work as a slot.
  • In its node specification mode, an HTMLviewPad
    frames different extractable document portions of
    its content document for different mouse
    locations so that its user may change the mouse
    location to see every selectable document
    portion.
  • Since each extracted Web component uses an
    HTMLviewPad to render its contents, it also
    allows users to specify any of its portions to
    work as its slot.
  • We call such a slot thus defined an HTML-node
    slot. The value of an HTML-node slot is the HTML
    view of the selected portion.
  • The HTMLviewPad converts ill-formed HTML into
    well-formed HTML to construct its DOM-tree.
    Therefore, you may connect an HTMLviewPad to an
    HTML-node slot to view the corresponding HTML
    view.
  • If the HTML-node slot holds an anchor node, the
    HTMLviewPad connected to this slot shows the
    target Web page.

110
  • The HTMLviewPad allows you to suspend the
    rendering of its contents. In this mode, you may
    use an HTMLviewPad with an HTML view as a blank
    pad with an arbitrary size.
  • Such a pad wraps a Web application, providing
    slots for the originals input forms and output
    text strings.
  • We call such a pad a wrapped Web application.
  • Since a wrapped Web application is such a pad
    that allows you to change its primary slot
    assignment, you may specify any one of its slots
    to work as a primary slot.

111
Explicit Slot Definition
meme pool (2D 3D)
userB
userA
drag drop
drag drop
redistribution
reediting
userC
112
HTML and Web Applications
HTML
  • ltagt
  • ??????
  • ???????
  • ltbgtlt/bgt
  • ????
  • ltcgtlt/cgt
  • lt/agt

?
????
Web server
Internet
113
Web Browser and DOM
  • HTML
  • Text file for a Web page
  • DOM
  • Document Object Model
  • Internal tree
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